Problem: $5r + 6s - 4t + 10 = -8s - 10t - 5$ Solve for $r$.
Combine constant terms on the right. $5r + 6s - 4t + {10} = -8s - 10t - {5}$ $5r + 6s - 4t = -8s - 10t - {15}$ Combine $t$ terms on the right. $5r + 6s - {4t} = -8s - {10t} - 15$ $5r + 6s = -8s - {6t} - 15$ Combine $s$ terms on the right. $5r + {6s} = -{8s} - 6t - 15$ $5r = -{14s} - 6t - 15$ Isolate $r$ ${5}r = -14s - 6t - 15$ $r = \dfrac{ -14s - 6t - 15 }{ {5} }$